Radio controlled navigation apparatus



July 9, 1935. F. E. NlCKEL RADIO CONTROLLED NAVIGATION APPARATUS Filed April 6, 1931 ummbhv TIME .Fzm J INVENTOR Fez-05am? EMU/(EL ATTORNEY Patented July 9,' 1935 s nsmoyoo t me? 41 1) NAVIGATION "APPARATUSI Frederick Er l qichel g l San Diego, Calif ass ignor of one-fourth to llaymond A." Keirle and onefourth to fWilliam, Diego, Calif.

L' lhillips as r San Application Ami-6;1931,1sirii1im' 2iso8 I commie. (cream-i1);

i My present inventionrelates radio controlled navigation apparatus, and is 'animprovementxif the apparatus shown in my copending application foriimprovementfor radio controlled navi gation apparatus, Serial No. 506,118 1 My device is particularly adapted. for the navigation of ships and of aircraft. i The objects of; my presentinvention are:

Eirst, toprovidea radio controlled means' for .use; on a craft-for ascertaining its di'recti'oniof movement and its position inconjunction with the known location of radio transmitting stations;

Second, to provide a radioreception device for amcraftywhich provides luminous visual indications of the fact that thecraft is progressing inc a direct line with a given transmitting station; Third, to provide means for indicating visually the direction thecraft must :be turned inorder to align it with the direct line from'a given transmitti-ng station"; a v, r 1

M Fourth, to provide two receiving antennae of such construction that the receptive quality of one will predominate over that of thegother at all-times that the craft is in-alignment; with the given radio transmitting station,-andreceiving means :associated {therewith adapted to visually indicate such predominance;

to r e. mappmms' of.- this class in W iQh h amenn 1 maybeplaced in a relatively n rrow space; i a I i- V :SlXthgtO provide an apparatus inwhich the phase of the current in the radio receiving means is periodically changed' or reversed, and particularly in which the phasefof-the currentin-the predominating ntenna is reversed with respect to thatof the other antenna; g A f S eventh, to provide an apparatus; of thisclass in which the phase of the current inI-the radio reoeivingmeans is "periodicallylchangedgor reversed without the necessity of opening andclosm ithe antenna circuit? 7 Eighth, to provide novel'means {ror-Fefifecting such reversing of the'phase oi the current; i l

3 Ninth, to provide means in connection with the radio receiving apparatus "and the luminous in- I dicating mean s for alternatelyelectrically connecting the; output'of the radio receiving appajratus toeach of the indicating means, suchalterhating connecting of the radioreceiving apparatus changing simultaneously with the changing of the phase of the current in the radio receiving apparatus; and

"Tenth, to provide a device of; this class which :may -be equally readily mounted and operatedon aircraft, a anre c a ip a d; n -w ic dotted lines in 1.

,is relativelysimplein: operationilight in weight,

compact. inform; and. which will not readily deteriorate or'get out, of order.-. a

With these and-other objects in View aswill appearhereinaften. my invention consists of cer- 133L115; novel features of construction, combination and arrangement of parts and portions as will be hereinafter described indetail and particularly set forth in theappended claims, reference being had to ithe. accompanying drawing and to the characters of areferencethereon which form. a part of this application in which: n v 1 V 1 Figure 1 is a wiring diagram and diagrammatic perspective illustration of my apparatus; Fig. 2 is aa diagrammatic View indicating the preferred relationship'oi thecloopvantenna to the craft; Fig. 3 'isia phase diagram withthe reversing and the phase lcha-ngingfapparatus in; the position ,shown in Fig. 1; and; Eigeis a phase diagram with the phase changing "apparatus r-otated from theposition shown in Fig. 1. i

Like oharactersgofu reference refer to similar parts and portions throughout the views of the drawing; 1 g i .The antennae I and 2, phase alternator 3, variable-condensers 4 and 5, primary induction coils :5;v 1, andB, secondary induction coils 9 and i0, radio receiving apparatus ll, steering indicators pl.2,.distributor' l3, and driving motor l4,'form the principal parts and portions of my apparatus;

7 Injmy present invention I provide a loop an- TtennaJI of the conventional directionfinding type comprising. a'number of turns of'wirewoundin acommon plane, mounted with'its plane at right angles t0 ther10ngitudinal axis or direction of j movementof the craft W, the longitudinal movement of the craft being indicated by the dash line in Fig.2. The primary induction coil 6 and the secondaryqinduction coil 9 are preferably wound {on a cornmon form and are contained in a metal shield, such as aluminum, represented by the The primary induction coil 6 is connected to the loop antenna i with the variable condenser 4 in series therewith, the variable condenser 4 being used to tune the antenna ;circuit to the transmittingstationfdesired, The antenna-Lisof the conventional single or multiple wiretype and ismounted on the craft W in any ;convenient'manner.. The primary induction coils l and :8 are connected inseries with the variable condenser 5,-andare in turn connected to the antenna 2 and'the ground; The ground may be of any conventional construction. However, when 1 any apparatus is mounted-on aircraftZ-it is-prerelia e t new co n e is inthe P ac t e it the longitudinal axis of the coils 'I and 8 The induction coils 1 and B are so connected in series that the radio frequency current induced into thecoil Ii] by the coil 8 will be out of phase with that of the current induced in the coil I U by the coil I. The antenna I with its induction coil 6, and the antenna 2 with its induction coils I and 8 are tuned to the same radio frequency, signal, that is, the same radio transmitting station by the variable condensers 4 and 5, respectively, so that the radio frequency energy induced in the coil 9 from the antenna I *and that induced in the coil I,from theantenna 2 is that of thesame transmitting station.

The phase alternator 3 consists of two semicircular non-magnetictmetal shields 3a and L3?) in the form of flat'disos, mounted 180 opposite to each other on a shaft I5 havingvits' longitudinal axis parallel to the-longitudinal axisof the coils I, 3, and I0, and connected to the motor lfii The metal shield 3a: is-adapted'to pass between the coils l and I0, while the shield 3bzis adapted to pass between-the coils 8. andllfl, as

they are rotated by the motor I4. When such a shield is placed between either the'coils 'l and Ii], or 8, and I5, inductive coupling between ,the'coils between which the shield is positioned'is pre vented because the magnetic lines of force,which affect such coupling will notpass therethrough. Thus the purpose of this alternator is to permit the radio frequency currents carried by the coils I and 3 to be alternately induced into the coil I0. Since the coils I and 8 areso connected together that the current induced in the coil III by the coil 8' is 180 out of phase with that'induced in the coil III by the coil I, the phase-of the current induced in the coil II received'by the antenna 2 willbe reversing periodically at a rate depending upon the rate at which the discs 3a and Share rotated; -i

The secondary coils 9 and I0 are connected in series and are in turn connectedto the input of the receiver I I, which may be any: sensitive receiver, but in its preferred construction comprises a sensitive multi-stage radio frequency am plifier using screen grid vacuum tubes-a regenerative detector, capable of causing radio-frequency oscillations in its associated circuit, and one or more stages of audio frequency amplification,- the output of which is connected to the indicating means through the distributor I3. The radio frequency current induced in the coil!) is that carried by the coil 6 and received by the antenna I, while the radio frequency current inducedin thecoil It is that carried by the coils -'I and 8, and received by the antenna 2. 'Thus the coils 9 and I I] will be carrying radio frequency current I received from two separate sources,

namely, the antennae I and 2; Since each of the antennae! and 2 is tuned to-receive radio frequency energy from the same transmitting 'station, 'the frequency of the current induced and ;carried by the coils 9 and III is that of the same station, thus eliminating the occurrence of beat frequencies which would result if the-antennae and is-in turn connected to ceiver- II, and that when the I and '2 is each tuned to different transmitting stations of different frequencies. It will be here noted that the phase of the current induced into the coil I9 from the coils land 8 will be alternately in and out of phase with the current induced into the coil 9 by the coil 6. The operation of the device is dependent upon this reversing of the phase of the current induced from one antenna with respect to that of the other antenna as will be hereinafter described.

- The output of the receiver II is associated with a circuit including the steering indicator I2,

. tributor I3 is mounted on the shaft I5 and con-' sists of an insulated disc I 3a which is provided around 180 of its circumference with an electricallyconductive segment I322. The distributor I3 is connected to the output of the receiver II through a collector ring I6 and the brush ISa which bears upon the collector ring IS. The neon glow lamp,designated L, is connected across the 'secondaryof an audio frequency transformer II, while the neon glow lamp, designated R.,is connected across the secondary of an audio transformerlB. One-lead to each of the primaries of the transformers I7 and I8 is connected together one of the output terminals of the receiver I I. The remaining terminal of the primary of the transformer I1 connects to a brushI3c which bears against the cir-'- cumference of the distributor I3; The remaining terminal of the transformer I8 connects to a second brush I3d positioned diametrically opposite to the brush I3 0, the brush ISd also bearing upon the circumference of the distributor I3.

These brushes are adapted to alternately engage the electrically conductive segments I3b for'alternatelyconnecting the transformers I7 and I8 to the output of the receiver II. The electrically conductive segment I3?) is so positioned on the insulation I 3a that the changing of the connection of the receiver to the transformers I I and I8 takes place simultaneously with the reversing'of the phase-of the current induced in the coil IIl'. Thus as the phase of the current induced in the coil I0 is reversed, the output current of therec'eiver II is connected to the oppositeone of the transformers than it was previously." Referring to Figure 1, it will be noted that when the distributor I3 and the phase alternator 3 are in the position shown, the current induced in the coil I0 is that of the coil 8 at which time the transformer I1 is connected to the output of the recurrent induced in the coil I0 is that of the coil 7, the transformer I8 is connected to-the' receiver I I. It Will also be noted that the speed of rotation of the shaft carrying'the phase alternator 3 and the distributor "I3 is relatively high,preferablyin the orderof 3600 R. P. M. Due to this rapid rotation of the phase alternator 3 and the distributor I3, the lamps I2 will'appear to be illuminated continuouslyand will not appear to flicker although 'they are alternately illuminated,

* Before describing the operation of the device,

it is pointed out that when the plane of the loop antenna'I is at'right anglesto a line adjoining the fantenna and the transmitting station, the radio frequency current in the antenna and asso- "ciated circuits will be practically zero, and when the plane of the loop is in line or parallel with a Consider first that the craft W is progressing.

is rotated in a clockwise position from the position of zero current, that is; when the'plane of the loop is perpendicular to" theline from the transmltting station, will bel80 opposite to that when the: loop is rotated to a counterclockwise position from the position of zero current" Incontradistinction to the phase relation of the current supplied'bya loop antennawhen'theantenna is rotated wthe phase of the' current flowing. in the conventional antenna, such as the antenna 2, "is

independent,.a's is the strength of thecurrent, of

thexpo'sition of the antennarelative to the transmitting stationi'ln view oftheabove facts,1:the

operation of the device'is as follows:

directly toward the transmitting station, thatv is, on za line with the transmitting station, then, as previously pointed out,the current flow. in the loopantenna I and the coil 6 will be practically zerc'jand alligof the radio frequency energylsuppliedto the receiver II will be that of the 'an-- tenna' 2; When the itphase alternator 3 and the distributor I3 are in the position shown in Fig. l,

the radio frequency current supplied to the receiver l I is induced into the coil In by the coil 8 and'the output ofthe receiver is connectedto the transformer I115 the neon glow lamp L will be illuminated to 'afcertain intensity depending upon: the; amount of current supplied .to thereceiverbythe coil- I6; Now if the phase alternator 3 and distributor"l3"are considered to be rotated 180, the radio frequency current supplied to the receiver; Itis induced into the boil '18 by thezcoilj I. Thus, the phase of the radio frequency.currentsupplied to'the receiver II is reversed l80, but this reversing does not affect the strength-of the o'utputcurrent of the receiver. However, the distributor I3 is in such a'position that the outputof the receiver II is now conn'ected to the. transformer I8; Thus the neon glow lampR. will be illuminated to thesame intensity as the lamp L was previously. Since the lamps L' and It are rapidly alternately connected to the receiver, they will appeartobe illuminated continuously, and when the craftW is progressing as herein considered,they will be illuminated to equal intensity indicating thatthe craft is on its course. p I

. Now'consider the craft .to be turnedv off tothe right 'of (the-course, which :is in eflect rotating theloop antenna I clockwise. The loop antenna 'Ihwill. bereceiving radio frequencycurrent in a proportion to the amount it is turned from the position of zero current. Thephase of the current willbe'as. represented by the curve A of Figure 3. The antenna 2 will also be receiving radio 3 frequency current, from .the same transmitting station, .and-'when the alternator 3 isin position shown in Fig. 1', the current of the antenna 2 is induced in the coil Ill by the coil 8.

The phase of. the current thus induced in the,

coil. II] will beas represented ,by curve B of .Fig. Since the coil. 9 also carriesthe current of the coil ill-and the .coil. II) also carries the current of the coil 9, and. since the curves representingthe'phase of the current flowing through the ci1s 9"and. I6 :from the antennae I and 2, respectively, areinUphase, the current supplied to the receiver II is the sum of the currents indueed in the coil 9 fromthe antenna I and the currentinduced in the coil. ill-from the antenna Z,..as"represented bythe curve C of Fig. 3; As.

. previously pointed out the output of the receiver isrconnected 'to.;,the transformer ll and the neon glow lamp L will be illuminated to an intensity representing the combined current of the antennae l and 2. When the phase alternator 3 and distributorlt are rotated 180-the phase of the current induced inthe coils 9 and It by the antenna l and the coil tend the antenna 2 and coil l, respectively, will be as represented by the curves A and B, respectively, of Fig. 4. It will be. notedthat'the current induced in the coil ill H the transformer I 8, the lamp R. will be illuminated toan intensity representing the difference 'of -.thecurrents-of,the antennae I and 2, which is considerably less than the former illumination of the lamp =L. Due to the rapidly alternately connecting of the transformers I? and I8 to thereceiver output, each of the lamps will appear to be illuminated continuously, and the lamp L, which receives the combined current of the "antennae' I and 2, will appear the brighter of the two, indicating that the craft W must be turned to the left to again alignit with the transmitting station. a I C 1 When the'craft is turned off tothe left of the course, theoperation is substantially the same as that described when the craft is turned to the right of the course. In thiscase thephase of the current induced in the coil 9 from the loop antenna I' is 180 opposite to that represented by curve A of Fig. 3 so" that the additive effect takes placewhen thealternator 3 is rotated 180 from theposition shown in Fig. l,.or when the phase of the current inducedv in the coil ID from the antenna 2 is as indicated by curve B of- Fig.4, and in this instance thedist'ributor i3 is-in such a position that the addifive-current is supplied to the transformer I8 which illuminates the neon glow lamp R, while the neon glow lamp L is now illuminated by the current representing the difierence oi the ourto be aligned with the transmitting station.

It is here pointed out that if the craft is prorentof the antennae I and 2. Thus the lamp R gressing away from the transmitting station, the

intensity of the illumination of the lamps L and R, will be reversed to what they normally should, so that, for example, when the lamp L isthe brighter of the two, which would normally'indicate that the craft should be turned to the left to again place it on its course, the pilot would automatically turn the craft to the left but*in so doing the lamp L would, instead of decreasing'in illumination would increase indicating that the craft is further to the left than before and the pilot, would therefore know that it is necessary to .turn the craft around 180. This condition takes place because the phase of the current in the loop antenna is 180 opposite to that which it would he were the craft progressing toward the transmitting station. This opposite phase condition causes the additive effect of the current from the two antennae-when the distributor I3 is 180 opposite to the position that it wouldbe when the additive effect occurs when the, craft is progressing toward the trans ly when flying toward or away from the transmitting station according to the position of the switch.

It will be here noted that the steering indicator lamps l2 may be replaced by the meter shown in my copending application, Serial No. 506,118 for indicating when the craft is on the proper course. However, in replacing the lamps l2 with the meter shown in the copending application itwould be necessary to make slight alterations in the distributor l3, and also to provide an additional rectifying means between the output of the receiver H and the distributor l3.

The application of my apparatus to a craft is substantially the same as that shown and described in connection with my copending application, Serial No. 506,118, although the operation of the device in my present invention differs from that in my copending application in that in my copending application I employ a meter for indicating when the craft is on its course, and furthermore that themeter indicates zero when the signal strength from the two antennae is equal. In my present invention I employ two neon glow lamps for indicating when the craft is on its course and the illumination of the two glow lamps will be equal when the signal strength of the antenna 2 in effect predominates over that of the antenna I.

Though I have shown and described a particular construction, combination and arrangement of parts and portions, I .do not wish to be limited to this particular construction, combination and arrangement, but desire to include in the scope of my invention, the construction, combination and arrangement substantially as set forth in the appended claims.

Having thus described my invention what I claim'as new and desire to secure by Letters Patent is:

1. In a radio navigation apparatus adapted to be carried on craft, a loop antenna and a nondirectional antenna and its ground mounted thereon, an inductance means and tuning means in electrical connection with said loop antenna, and a secondary inductance means inductively coupled with the loop antenna inductance means,

a pair of inductance coils, and a tuning means in electrical connection with thenon-directional antenna, and a secondary inductance coil in inductive coupling relation to each of the pairs of inductance coils, a shield means adapted to pass between each of said pair of inductance coils and the secondary inductance coil, said shieldmeans relatively disposed so as to pass alternately be.- tween the respective inductance coils, and means for operating said shield means whereby the phase of the oscillations induced in said secondary inductance coil is reversed with respect to those of the secondary inductance coil associated with said loop antenna. 1 V

2. In a radio navigation apparatus adaptedto be carried on craft, aloop antenna and anonadditive our;

directional antenna and itsgrourid mounted thereon, an inductance coiland tuning means in electrical connection with 'said'loop antenna and. a secondary inductance coil" inductively-coupled to the loop antenna inductance coil, said coils being containedwithin a metal shield, apair of inductancemeans each contained'within tubular metalshields, .and a tuning means in electrical connection with the non-directional antenna,

and a secondary inductance means contained withina tubular metalv shield and-positioned in longitudinalaxial alinement with said pair of induetance means forplacing said pair of induc tance. means in inductive coupling. relation to said secondary inductance means, and means for alternately shielding each of said inductance means fromsaid secondary inductancemeans whereby the phase of said secondary inductance means is reversed with respect to said secondary inductance coil. j r

3. In a radio navigation'apparatus adapted to be carried on craft, a loop antenna anda nondirectional antenna and its ground mounted thereon, aninductanoe coil and tuning means in electrical connection with-said loop antenna and a secondary inductance coil inductively coupled with the loop antennainductancelcoil, said coils being contained within a metal shield, .a pair of inductance means each being contained within tubular metal shields, and 'a tuning'means in electrical connection with the non-directional antenna, and a secondary inductance means contained within a tubular metal shield and positioned in longitudinal axial alinement with and between said pair of inductance means for placing said pair of' inductance means in inductive coupling relation o said secondary inductance means, substantially semi-circular metal shields rotatably mounted upon a shaft in arcuately offset relation so asto pass alternately between each of said pairs of inductance means and said secondary inductance means whereby the phase of said secondary inductance means is reversed with respect to said secondary inductance coil.

4. In a radio navigation apparatus adapted to be carried on a ,craft,a pair of radio oscillation collecting circuits, a directional antenna in one of said collecting circuits, a non-directional antenna in the other of said collecting circuits, a radio oscillation receiving means inductively coupled with both of said collecting circuits, and apparatus for reversing the phase of one of said collector circuits with respect to the other comprising, a pair of primary inductance means in one of said collector circuits, a secondary in- 5. In aradio navigation apparatus adapted toa be carried on craft, a directional antenna and a non-directional antenna and its ground mounted thereon, a primary inductance coil and tuning means electrically connected with one of said antennae, and a secondary inductance coil inductively connected with said primary inductance coil, said coils being contained within a metal shield, a pair of primary inductance means each contained within a tubular shield, and a tuning means electrically connected with the other antenna, and a secondary inductance means arranged within a tubular shield in longitudinal axial alinement with .saidpair Ofprimary inductancemeans, and means adapted topass be.-

tween said primary inductance means and said secondary inductance means for alternately shielding and permitting inductance coupling of said primary secondary inductance means whereby the phase of said secondary inductance means. is reversed with respect to said secondary inductance coil.

6. In a radio navigation apparatus adapted to be carried on craft, a directional antenna and a non-directional antenna andits ground mounted thereon, a primary inductance coil and tuning means electrically connected with one of said antennae, and a secondary inductance coil inductively connected with said primary inductance coil, said coils being contained within a inductance means with said metal shield, a pair of primary inductance means each contained within a tubular shield, and a tuning means electrically connected with the other antenna, and a secondary inductance means arranged within a tubular shield in longitudinal axial alinement'with said pair of primary inductance means, and a substantially semi-circular shield rotatably mounted upon a shaft adapted to pass alternately between said primary inductance means, and a motor for driving said shield whereby the phase of said secondary inductance means is reversed with that of the secondary inductance coil.

FREDERICK E. NICKEL. 

